TCEC Season 9 Superfinal Week 4

It's all over! In last week's post, TCEC Season 9 Superfinal Week 3, we left Stockfish leading Houdini by a score of +12-5=52, with 31 games still to be played. The 100th game finished this morning, giving a further score of +5-3=23. Adding those scores together gives us a total score of...

+12-5=52 after week three
+ 5-3=23 week four
--------
+17-8=75

...in favor of Stockfish. Congratulations to the Stockfish team on becoming the defacto, unofficial World Computer Chess Champion.

In my first report on the competition, Superfinal Underway, I took the results of the first few days...

In the nearly three days since the event started, the engines have played 12 complete games non-stop with Stockfish leading Houdini by +3-0=9.

...and extrapolated to a crushing final score of +25-0=75. I was right about the number of draws, but dead wrong about the margin of victory. Houdini won twice in the second week and three times in each of the two following weeks to put up a fight, although the final outcome was never in doubt.

The controversial scoring of game 17 in Superfinal Week 2, where Stockfish was awarded a win in a game that both engines evaluated as a draw, prompted some sticklers to declare a final score of +16-8=76. I'll give the event's organizers the privilege of scoring the game according to how they interpret the rules. Chessdom.com reported the result of the event in Stockfish is the TCEC Season 9 Grand Champion

Stockfish, the open source chess engine by Tord Romstad, Marco Costalba, Joona Kiiski, and Gary Linscott, is the winner of the 2016 edition of the Top Chess Engine Championship. Stockfish 8 won the 100 games Superfinal match against Houdini 5 with a total score of 54,5 – 45,5. This is the second TCEC gold medal for Stockfish and it comes after the title in Season 6 and two runner up positions in Seasons 7 and 8. The third position in 2016 is for the ex-champion Komodo.

Given that Stockfish is open source -- anyone can go to its site and download the latest version for free -- why would someone pay money for a commercial engine like Houdini? That is a question that I can't answer. The day before the TCEC ended, Chessbase.com ran the following 'news' item on the home page of the English version of the site.

'Houdini 5 won the "Top Chess Engine Championship"
(TCEC, Season 9)'

The blurb neglected to mention that Houdini won the rapid event that preceded the Superfinal. As I write this, there has been no mention by Chessbase of the Superfinal result. The 'Impressive...' link went to a product page offering Houdini for Euro 99.90. Impressive, indeed.